Nonane triisocyanate (NTI or 4-isocyanatomethyl-1,8-octane diisocyanate) is a known material. Various uses for NTI have been suggested. See, e.g., U.S. Pat. Nos. 4,314,048; 5,714,564; 5,854,301; 6,084,051; 6,090,939; 6,100,326; 6,291,578; 6,399,691; 6,432,485; 6,433,072; 6,531,535; 6,566,444; and 6,605,669.
A market need exists for a high functionally, high NCO content, low unblocking temperature polyurethane crosslinker. Pyrazole-blocked isocyanates unblock at relatively low temperatures (see, e.g., U.S. Pat. Nos. 4,976,837, 5,246,557, 5,521,272 and 5,986,033). The fully blocked reaction product of nonane triisocyanate and a pyrazole meets the market need as far as functionality, NCO content and unblocking temperature but is not soluble in commercially used coating solvents (see U.S. application Ser. No. 10/723,646, filed on the same day as the present application) and as a result has limited usefulness in the coating area.